Citi analyst Tyler Radke lowered his recommendation on MicroStrategy to “sell” from “neutral,” warning investors in a Tuesday research note the company’s recent bitcoin euphoria may be overextended, according to Seeking Alpha.

Radke cited CEO Michael Saylor’s “disproportionate focus” on bitcoin as a potentially troubling trend for the business intelligence company. He also said MicroStrategy’s planned $400 million debt offering to fund additional bitcoin purchases signals “incremental risk to the story.”

Insider selling also contributed to Radke’s eyeing a $250 price target (still above his previous MSTR target of $200).

Shares of MSTR were down more than 10% to $300.86 in recent trading. The shares have more than doubled since August, largely driven by Saylor’s foray into bitcoin.